Vane rotary compressor

ABSTRACT

Disclosed herein is a vane rotary compressor in which a fluid such as a refrigerant is compressed, with the volume of a compression chamber being reduced during the rotation of a rotor. In addition, disclosed is a vane rotary compressor having a configuration such that a space between a cylinder and a housing is divided into a high-pressure chamber, from which a high-pressure refrigerant is discharged, and an oil storage chamber in which oil included in the refrigerant is separated and stored, and having an oil decompression structure using a gap between a rotor and a head portion.

FIELD OF INVENTION

The present invention relates to a vane rotary compressor in which a fluid such as a refrigerant is compressed, with the volume of a compression chamber being reduced during the rotation of a rotor. More particularly, the present invention relates to a vane rotary compressor having a configuration such that a space between a cylinder and a housing is divided into a high-pressure chamber, from which a high-pressure refrigerant is discharged, and an oil storage chamber in which oil included in the refrigerant is separated and stored.

BACKGROUND

A vane rotary compressor is used for an air conditioner and the like, and compresses a fluid such as a refrigerant to supply the outside with the compressed fluid.

FIG. 1 is a sectional view schematically illustrating a conventional vane rotary compressor disclosed in Japanese Unexamined Patent Application Publication No. 2010-31759 (published on Feb. 12, 2010). FIG. 2 is a sectional view taken along line A-A of FIG. 1.

As shown in FIG. 1, the conventional vane rotary compressor 10 includes a housing H which is configured of a rear housing 11 and a front housing 12 while defining an external appearance thereof, and a cylindrical cylinder 13 which is accommodated within the rear housing 11.

In this case, the cylinder 13 has an inner peripheral surface having an oval sectional shape, as shown in FIG. 2.

In the inside of the rear housing 11, the cylinder 13 is coupled, at the front thereof, with a front cover 14 while being coupled, at the rear thereof, with a rear cover 15.

In this case, a discharge space Da is defined between an outer peripheral surface of the cylinder 13, an inner peripheral surface of the rear housing 11 facing the same, the front cover 14, and the rear cover 15.

The front cover 14 and the rear cover 15 are rotatably mounted with a rotational shaft 17 which passes through the cylinder 13.

In addition, the rotational shaft 17 is coupled with a cylindrical rotor 18, and the rotor 18 rotates within the cylinder 13 along with the rotational shaft 17 during the rotation of the rotational shaft 17.

As shown in FIG. 2, a plurality of slots 18 a is radially formed on an outer peripheral surface of the rotor 18, a vane 20 is slidably accommodated in each of the slots 18 a, and lubricant oil is supplied within the slot 18 a.

When the rotor 18 rotates by the rotation of the rotational shaft 17, a tip portion of the vane 20 protrudes outward of the slot 18 a and comes into close contact with the inner peripheral surface of the cylinder 13.

In this case, a plurality of compression chambers 21 is divided and formed of which each is defined by the outer peripheral surface of the rotor 18, the inner peripheral surface of the cylinder 13, a pair of vanes 20 adjacent to each other, and a facing surface 14 a of the front cover 14 and a facing surface 15 a of the rear cover 15, which face the cylinder 13.

In the case of the vane rotary compressor, an intake stroke is a stroke in which the volume of the compression chamber 21 is enlarged, whereas a compression stroke is a stroke in which the volume of the compression chamber 21 is reduced, according to the rotation direction of the rotor 18.

As shown in FIG. 1, the front housing 12 is formed, at an upper portion thereof, with a suction port 24 while being formed therein with a suction space Sa which communicates with the suction port 24.

The front cover 14 is formed with an inlet 14 b which communicates with the suction space Sa, and a suction passage 13 b which communicates with the inlet 14 b is formed to axially pass through the cylinder 13.

As shown in FIG. 2, the outer peripheral surface of the cylinder 13 is formed, at opposite sides thereof, with discharge chambers 13 d which are recessed inwards.

In this case, a pair of discharge chambers 13 d communicates with the compression chambers 21 through associated discharge holes 13 a, and forms a portion of the discharge space Da.

The rear housing 11 is formed with a high-pressure chamber 30 which is divided by the rear cover 15 and into which a compressed refrigerant is introduced. That is, the inside of the rear housing 11 is divided into the discharge space Da and the high-pressure chamber 30 by the rear cover 15. In this case, any one of the pair of discharge chambers 13 d is formed with an outlet 15 e which communicates with the high-pressure chamber 30.

Accordingly, when the rotor 18 and the vanes 20 rotate along with the rotation of the rotational shaft 17, a refrigerant is sucked from the suction space Sa via the inlet 14 b and the suction passage 13 b into each compression chamber 21.

Subsequently, the refrigerant compressed by the reduction in the volume of each compression chamber 21 is discharged into each discharge chamber 13 d through the associated discharge hole 13 a to be introduced into the high-pressure chamber 30 through the outlet 15 e, and is then supplied to the outside through a discharge port 31.

Meanwhile, the high-pressure chamber 30 is provided with an oil separator 40 for separating the lubricant oil from the compressed refrigerant introduced into the high-pressure chamber 30.

An oil separation pipe 43 is installed at an upper portion of a case 41, and is formed, at a lower portion thereof, with an oil separation chamber 42 into which the separated oil is dropped.

In this case, the oil in the oil separation chamber 42 flows down into an oil storage chamber 32, which is formed in a lower portion of the high-pressure chamber 30, through an oil passage 41 b.

The oil stored in the oil storage chamber 32 lubricates a sliding surface between the rear cover 15 and rotor 18 via a lubricant space of a bush, which supports a rear end of the rotational shaft 17, through an oil supply passage 15 d. Subsequently, the oil is reintroduced into the outlet 15 e through an oil return groove 45 by a difference in pressure between the discharge space Da and the high-pressure chamber 30.

Incidentally, in the conventional vane rotary compressor, if the number of the housings, such as the rear housing 11, the front housing 12, the cylinder 3, the front cover 14, and the rear cover 15, is increased, an increase in the number of manufacturing processes is caused thereby. Furthermore, since a coupling portion between each of the housings should be sealed, it is difficult to maintain a seal, thereby resulting in an increase in costs.

In addition, there is a problem in that the overall length of the package is increased due to the formation of the oil storage chamber 32 in the rear housing 11. Furthermore, since the conventional vane rotary compressor has a complicated decompression structure in which the oil separated from the refrigerant reaches the outlet 15 e from the rear end of the rotational shaft 17, there is a problem of resulting in an increase in costs due to an increase in the number of processes.

SUMMARY

Accordingly, the present invention has been made in view of the above-mentioned problem, and an object thereof is to provide a vane rotary compressor having a 3-piece structure that includes a cylinder, a housing which is integrally formed with a cylinder portion accommodating the cylinder and a first head portion to close one side of the cylinder portion, and a second head portion to close the other side of the cylinder portion.

Another object of the present invention is to provide a vane rotary compressor having a configuration such that a space between an inner peripheral surface and an outer peripheral surface of a cylinder portion is divided into a high-pressure chamber, from which a high-pressure refrigerant is discharged, and an oil storage chamber in which oil included in the refrigerant is separated and stored.

A further object of the present invention is to provide a vane rotary compressor having a decompression structure which is formed using a gap between a rotor and a head portion.

In accordance with an aspect of the present invention, a vane rotary compressor includes a hollow cylinder; a housing including a cylinder portion which is formed with a space portion to mount the cylinder, and a first head portion which is formed integrally with the cylinder portion so as to close one axial side of the cylinder portion; a second head portion to close the other axial side of the cylinder portion; a rotor which is mounted within the cylinder and rotates by the power of a drive source; a plurality of vanes which protrudes from an outer peripheral surface of the rotor toward an inner peripheral surface of the cylinder and divides a hollow portion of the cylinder into a plurality of compression chambers; a high-pressure chamber which is formed in one side of the housing, from which a high-pressure refrigerant compressed in each of the compression chambers is discharged, and which is formed with a discharge hole communicating with a discharge port; and an oil storage chamber which is formed in the other side of the housing and stores oil separated by an oil separation pipe provided at the discharge port.

Here, the high-pressure chamber may include a muffler space which is formed to protrude from one side of an outer peripheral surface of the cylinder portion, and the discharge hole may be formed at one side of the muffler space.

In addition, the oil storage chamber may be formed on an outer peripheral surface of the housing to radially protrude therefrom.

In this case, an oil guide hole may be formed to extend from one side of the oil storage chamber to one side of a mounting groove to which a rear end of a rotational shaft of the rotor is mounted.

In addition, a first expansion groove may be formed along an edge of the mounting groove.

In this case, a second expansion groove may be formed in the form of an involute curve to extend radially outwards from one side of the first expansion groove.

Also, the rotor may be formed with a plurality of oil passages which axially penetrates the rotor so as to communicate with the second expansion groove, and the second expansion groove may be located at a position corresponding to the oil passages.

In this case, an extension groove may be formed along an edge of an insertion hole into which a front end of the rotational shaft is inserted, so as to communicate with the oil passages.

Meanwhile, at least one second expansion groove may be spaced radially outwards from the first expansion groove and formed along a circumferential direction thereof.

In this case, the second expansion groove may be formed in the form of a circular arc corresponding to a region between a suction hole and an outlet formed at one side of the cylinder in a compression rotation direction of the rotor.

In addition, the rotor may be formed with a plurality of oil passages which axially penetrates the rotor so as to communicate with the second expansion groove, and the second expansion groove may be located at a position corresponding to the oil passages.

In this case, an extension groove may be formed along an edge of an insertion hole into which a front end of the rotational shaft is inserted, so as to communicate with the oil passages.

Also, one end of each of the vanes may be hinge-coupled to one side of the outer peripheral surface of the rotor, and the other end thereof may come into contact with the inner peripheral surface of the cylinder, depending on the rotation of the rotor.

In this case, the hollow inner peripheral surface of the cylinder may be formed in the form of an involute curve along a circumferential direction thereof.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

BRIEF DESCRIPTION OF THE DRAWING(S)

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings.

FIG. 1 is a sectional view schematically illustrating a conventional vane rotary compressor.

FIG. 2 is a sectional view taken along line A-A of FIG. 1.

FIG. 3 is a perspective view illustrating a vane rotary compressor according to an embodiment of the present invention.

FIG. 4 is a longitudinal-sectional view illustrating the vane rotary compressor according to the embodiment of the present invention.

FIG. 5 is a perspective view illustrating a housing according to the embodiment of the present invention.

FIG. 6 is a sectional view illustrating a state in which a cylinder and a rotor are mounted in the housing of FIG. 5.

FIG. 7 is a sectional view schematically illustrating a coupling between a cylinder and a rotor according to another example of the present invention.

FIG. 8 is a perspective view illustrating a second head portion according to the embodiment of the present invention.

FIG. 9 is a perspective view illustrating the vane rotary compressor according to the embodiment of the present invention, when viewed from the rear.

FIG. 10 is a partially enlarged view illustrating an oil decompression structure according to the embodiment of the present invention.

FIGS. 11A to 11D are schematic views illustrating various examples of a second expansion groove formed in the second head portion.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Reference will now be made in detail to a vane rotary compressor according to an embodiment of the present invention, examples of which are illustrated in the accompanying drawings. The drawings are not necessarily to scale and in some instances, proportions may have been exaggerated in order to clearly illustrate features of the embodiment.

In addition, terms to be described later are terms defined in consideration of functions of the present invention, and these may vary with the intention or practice of a user or an operator. Therefore, such terms should be defined based on the entire content disclosed herein.

Also, the present invention will be described with respect to the illustrative embodiments, and it should be understood that numerous other modifications and variations may be devised by those skilled in the art that will fall within the intrinsic aspects of the embodiments. Furthermore, various variations and modifications are possible in concrete constituent elements of the embodiments. In addition, it is to be understood that differences relevant to the variations and modifications fall within the spirit and scope of the present invention defined in the appended claims.

An Embodiment

A vane rotary compressor according to an embodiment of the present invention has a 3-piece structure configured by a cylinder, a housing of which one side is opened so as to accommodate the cylinder, and a second head portion to cover and close an opening portion of the housing.

The housing includes a cylinder portion which is formed therein with a space portion so as to accommodate the cylinder, and a first head portion which is integrally formed at one side of the cylinder portion so as to close one side of the space portion of the cylinder portion.

In this case, when a head portion to close the space portion of the cylinder portion in the front is referred to as “front head portion” and a head portion to close the space portion of the cylinder portion in the rear is referred to as “rear head portion”, the front head portion may also be formed integrally with the cylinder portion and the rear head portion may also be formed integrally with the cylinder portion, in the housing according to the embodiment of the present invention.

Accordingly, although the embodiment of the present invention shown in FIGS. 3 to 10 illustrates an example in which the housing is formed by integral formation of the front head portion (hereinafter, referred to as “first head portion”) and the cylinder portion, the housing may also be formed by integral formation of the rear head portion (hereinafter, referred to as “second head portion) and the cylinder portion as occasion demands.

Hereinafter, the present invention will be described in detail with reference to the embodiment illustrated in FIGS. 3 to 10.

FIG. 3 is a perspective view illustrating a vane rotary compressor according to an embodiment of the present invention. FIG. 4 is a longitudinal-sectional view illustrating the vane rotary compressor according to the embodiment of the present invention.

As shown in FIGS. 3 and 4, the overall external appearance of the vane rotary compressor 100 according to the embodiment of the present invention is defined by a coupling of a housing 300 and a second head portion 400.

The housing 300 includes a cylinder portion 310 which is formed therein with a space portion 311, and a first head portion 320 which is formed integrally with the cylinder portion 310 in the axial front thereof to close the front of the space portion 311. The space portion 311 is mounted with a hollow cylinder 200.

In this case, the cylinder 200 is mounted therein with a rotational shaft 530 which rotates by the power of a drive source, a rotor 500 which rotates along with the rotational shaft 530 by receiving a rotation force from the rotational shaft 530, and a plurality of vanes 600 which is coupled on an outer peripheral surface of the rotor 500 to be able to protrude therefrom.

In addition, the second head portion 400 is coupled to the axial rear of the housing 300 to close the rear of the space portion 311.

Meanwhile, the first head portion 320 of the housing 300 is provided, on an outer peripheral surface thereof, with a suction port 330 to suck a refrigerant from the outside and a discharge port 340 to discharge a high-pressure refrigerant compressed within the cylinder 200 to the outside, which are spaced apart from each other.

In this case, the first head portion 320 is extendably formed, at a front center thereof, with a pulley coupling portion 910 so as to couple a pulley 900 of an electromagnetic clutch (not shown).

FIG. 5 is a perspective view illustrating the housing according to the embodiment of the present invention, when viewed from the rear.

As shown in FIG. 5, the housing 300 according to the embodiment of the present invention includes the cylindrical cylinder portion 310 which is formed therein with the space portion 311 so as to accommodate the cylinder 200, and the first head portion 320 which is integrally formed in the front of the cylinder portion 310 to close the front of the space portion 311.

In this case, the center of the first head portion 320 is formed with a penetrating insertion hole 321 into which a front end of the rotational shaft 530 is inserted. One side of an inner side surface of the first head portion 320 is formed with a suction groove 323 which communicates with the suction port 330 and extends in a circumferential direction C at a predetermined angle.

In addition, the inner side surface of the first head portion 320 is formed with an extension groove 322 which extends along an edge of the insertion hole 321 at a predetermined angle. The extension groove 322 serves to lubricate the rotational shaft 530 and will be described later.

A muffler space 710 is formed to protrude from one side of an outer peripheral surface of the cylinder portion 310, and one side of the muffler space 710 is formed with a discharge hole 711 which communicates with the discharge port 340.

In this case, after pulsation and noise are reduced while a high-pressure refrigerant compressed in each compression chamber 210 to be described later is introduced into the muffler space 710, the refrigerant flows toward the discharge port 340 through the discharge hole 711.

Meanwhile, one side of a side wall of the cylinder portion 310 is formed with a first oil storage chamber 810 which protrudes outwards, and oil, which is separated by an oil separation pipe 350 (see FIG. 6), is introduced into and stored in the first oil storage chamber 810.

FIG. 6 is a sectional view illustrating a state in which the cylinder and the rotor are mounted in the housing of FIG. 5.

Here, the bold arrow indicated in FIG. 6 indicates the suction and discharge direction of the refrigerant, the solid line arrow indicates the rotation direction of the rotational shaft, the alternately long and short dashed line arrow indicates the flow of the high-pressure compressed refrigerant, and the dotted line arrow indicates the flow of the refrigerant from which the oil is separated while passing through the oil pipe.

As shown in FIG. 6, a hollow portion of the cylinder 200 is formed to be slightly off-centered to one side from a center of the cylinder 200 in which the rotational shaft 530 is installed.

In this case, the rotor 500 with the vanes 600 is inserted into and mounted in the hollow portion of the cylinder 200, so that the hollow portion of the cylinder 200 forms a compression space in which the introduced refrigerant is compressed by the rotation of the rotor 500.

One side of the cylinder 200 is formed with a suction hole 220.

In this case, one side of the suction hole 220 communicates with the suction groove 323 of the first head portion 320, and the other side thereof communicates with one side of the compression space in the cylinder 200.

Accordingly, the refrigerant, which is sucked through the suction port 330 from the outside, passes through the suction groove 323 of the first head portion 320 and the suction hole 220 of the cylinder 200 in turn and is then introduced into the hollow portion of the cylinder 200.

The rotor 500 is coupled to the rotational shaft 530, which is connected to a clutch (not shown) driven by a drive motor (not shown) or an engine belt (not shown), to axially rotate along with the rotational shaft 530. In this case, the rotor 500 is formed with a plurality of oil passages 510 which axially penetrates the rotor 500.

In addition, the rotational shaft 530 is mounted along a central axis of the cylinder 200. Accordingly, the rotor 500 deviates slightly to one side from the center of the hollow portion of the cylinder 200, thereby eccentrically rotating within the hollow portion of the cylinder 200.

The cantilever type vanes 600 are spaced apart from each other and are hinge-coupled to the outer peripheral surface of the rotor 500. In this case, one side of each vane 600 is hinge-coupled to an outer peripheral surface slot 520 of the rotor 500, whereas a tip portion of the other side of the vane 600 is spread toward the inner peripheral surface of the cylinder 200 by the pressure of the refrigerant during the rotation of the rotor 500. As a result, the compression space is divided into a plurality of compression chambers 210.

That is, each compression chamber 210 is formed by a space defined by a pair of adjacent vanes 600, the outer peripheral surface of the rotor 500, and the inner peripheral surface of the cylinder 200. In this case, a front end and a rear end of the compression chamber 210 are closed by the first head portion 320 and the second head portion 400, respectively.

During the rotation of the rotor 500, the tip portion of the vane 600 rotates together in the rotation direction of the rotor 500 along an inner side wall of the hollow portion.

In this case, as the rotor 500 is located to be off-centered within the hollow portion, the volume of the compression chamber 210 is reduced, with a clearance between the outer peripheral surface of the rotor 500 and the inner side wall of the hollow portion being gradually narrowed. Consequently, the refrigerant in the compression chamber 210 is compressed.

A discharge portion 720, from which the high-pressure compressed refrigerant is discharged, is formed to be recessed from one side of the outer peripheral surface of the cylinder 200. The discharge portion 720 is formed, at one side thereof, with a plurality of penetrating outlets 721 which communicates with the compression chambers 210, whereas is formed, at the other side thereof, with a guide passage 730 to guide the high-pressure refrigerant toward the discharge port 340.

In this case, the muffler space 710 formed in the cylinder portion 310 of the above-mentioned housing 300 is located to correspond to one side of the guide passage 730.

Accordingly, the high-pressure refrigerant, which is discharged into the discharge portion 720 through the outlets 721, is introduced into the muffler space 710 along the guide passage 730, and then flows through the discharge hole 711 toward the discharge port 340.

The oil included in the refrigerant is separated below the oil separation pipe 350 while the high-pressure refrigerant passing through the discharge hole 711 circles around along an outer peripheral surface of the oil separation pipe 350. The separated oil flows to and is stored in the first oil storage chamber 810 which is formed in the cylinder portion 310 of the housing 300.

In this case, the other side of the outer peripheral surface of the cylinder 200 is recessed in a predetermined shape to form a second oil storage chamber 820 which communicates with the first oil storage chamber 810 at a lower side thereof.

Here, the discharge portion 720, the guide passage 730, and the muffler space 710 form a high-pressure chamber 700 in which the high-pressure refrigerant flows in the vane rotary compressor 100. The high-pressure chamber 700 is formed in one side of a space between the cylinder portion 310 and the cylinder 200.

In addition, an oil storage chamber 800, which includes the first oil storage chamber 810 and the second oil storage chamber 820, is formed in the other side of the space between the cylinder portion 310 and the cylinder 200.

In this case, the high-pressure chamber 700 and the oil storage chamber 800 are divided by a contact surface 230 on which the outer peripheral surface of the cylinder 200 comes into close contact with the inner peripheral surface of the cylinder portion 310.

That is, in the vane rotary compressor 100 according to the embodiment of the present invention, the oil storage chamber 800 formed in the rear head in the related art is formed in the cylinder portion 310 of the housing 300 together with the high-pressure chamber 700.

Thus, it may be possible to compactly configure a package of the vane rotary compressor 100 according to the embodiment of the present invention.

In general, an upper space between the cylinder portion 310 of the housing 300 and the cylinder 200 is utilized as the high-pressure chamber 700, whereas a lower space between the cylinder portion 310 and the cylinder 200 is utilized as the oil storage chamber 800.

FIG. 7 is a sectional view schematically illustrating a coupling between a cylinder and a rotor according to another example of the present invention.

In accordance with another example of the present invention, a hollow inner peripheral surface of a cylinder 200′ may also be formed in the form of an involute curve as shown in FIG. 7.

In this case, the rotor 500 is installed in a hollow portion of the cylinder 200′ so that the inner peripheral surface of the cylinder 200′ and the outer peripheral surface of the rotor 500 have equal centers when viewed in section. That is, in the involute curve which is defined along the inner peripheral surface of the cylinder 200′, centers of a start point and an end point coincide with the center of the rotor 500. Consequently, it may be possible to reduce vibration and noise due to the eccentric arrangement of the rotor 500.

In this case, the inner peripheral surface of the cylinder 200′ is formed in the form of an involute curve in which a diameter of the cylinder 200′ is gradually decreased in the direction from the suction hole 220 toward the outlets 721.

Accordingly, along the compression rotation direction of the rotor 500 as depicted as the arrow, the volume of the compression chamber 210 formed between the vanes 600 is gradually reduced, with a clearance between the inner peripheral surface of the cylinder 200′ and the outer peripheral surface of the rotor 500 being gradually narrowed. Consequently, the refrigerant is compressed.

FIG. 8 is a perspective view illustrating the second head portion according to the embodiment of the present invention. FIG. 9 is a perspective view illustrating the vane rotary compressor according to the embodiment of the present invention, when viewed from the rear.

The second head portion 400 according to the embodiment of the present invention is coupled to the rear of the housing 300 to close the rear of the space portion 311 in the axial rear of the cylinder portion 310.

In this case, as shown in FIG. 9, the second head portion 400 is formed, at a center of an outer side surface thereof, with a shaft receiving portion 420 which protrudes outwards. In addition, as shown in FIG. 8, the second head portion 400 is formed, at a center of an inner side surface thereof, with a mounting groove 410 corresponding to the shaft receiving portion 420. The rear end of the rotational shaft 530 is inserted into and mounted to the mounting groove 410.

In this case, a first expansion groove 430 is formed along an edge of the mounting groove 410, and a second expansion groove 440 is spaced radially outwards from the first expansion groove 430 and is formed along the circumferential direction C.

The second expansion groove 440 is preferably formed in the form of a circular arc corresponding to a region in which an intermediate pressure is formed in the compression chamber 210, among compression regions between the suction hole 220 and the outlets 721 which are respectively formed at one side of the cylinder 200 along the compression rotation direction of the rotor 500.

Here, the “intermediate pressure” refers to, among the plural compression chambers 210, a pressure which is intermediate between the pressure in the compression chamber 210, in which the refrigerant is introduced through the suction hole 220 and begins to be compressed, and the pressure in the compression chamber 210 in which the refrigerant is discharged through the outlets 721 after a compression stroke is completed.

In this case, the first and second expansion grooves 430 and 440 serve to decompress the oil on a sliding surface between the rotor 500 and the second head portion 400. This will be described later.

Meanwhile, the oil stored in the oil storage chamber 800 flows to the shaft receiving portion 420. To achieve this, one side of the inner side surface of the second head portion 400 is formed with an oil guide hole 421 of which one side communicates with the oil storage chamber 800 and of which the other side communicates with the mounting groove 410 of the shaft receiving portion 420.

FIG. 10 is a partially enlarged view illustrating an oil decompression structure according to the embodiment of the present invention. Here, the arrow indicated by an alternately long and short dashed line indicates the flow direction of the oil.

The oil stored in the oil storage chamber 800 flows to the mounting groove 410 of the shaft receiving portion 420 through the oil guide hole 421 to lubricate the rear end portion of the rotational shaft 530, and flows forward along the outer peripheral surface of the rotational shaft 530.

In this case, the oil is first decompressed by a gap defined between the outer peripheral surface of the rotational shaft 530 and an inner peripheral surface of the mounting groove 410, and expands while being introduced into the first expansion groove 430.

The oil introduced into the first expansion groove 430 lubricates the sliding surface between the rotor 500 and the second head portion 400 while being spread radially outwards by the rotation of the rotor 500.

In this case, the oil is secondly decompressed by a gap between the rotor 500 and the second head portion 400, and expands again while being introduced into the second expansion groove 440. Subsequently, the oil is thirdly decompressed on the sliding surface between the rotor 500 and the second head portion 400 while being spread outwards.

The oil, which lubricates the sliding surface between the rotor 500 and the second head portion 400, lubricates a sliding surface between the rotor 500 and the first head portion 320 by moving forward through each oil passage 510 of the rotor 500 due to the communication of the oil passage 510 with the second expansion groove 440.

In this case, the oil flows to the insertion hole 321 through the extension groove 322, which communicates with the oil passage 510, to lubricate the front end portion of the rotational shaft 530.

In this case, the oil is decompressed again by a gap between an outer peripheral surface of the front end portion of the rotational shaft 530 and an inner peripheral surface of the insertion hole 321, and is then sucked into each compression chamber 210 together with the refrigerant. Subsequently, the oil goes through the above-mentioned processes again.

That is, in the vane rotary compressor 100 according to the embodiment of the present invention, by configuring multiple decompression passages for the oil through the gap between the rotor 500 and the second head portion 400 and the expansion grooves 430 and 440, it may be possible to avoid a problem of needing separate parts to form the complicated decompression passage or increasing process costs in the related art.

In this case, by properly selecting the shape of the second expansion groove 440, any region of the sliding surface between the rotor 500 and the second head portion 400 may be locally and intensively lubricated, or the second and third decompressions may be continuously performed.

FIGS. 11A to 11D are schematic views illustrating various examples of the second expansion groove formed in the second head portion.

Here, FIG. 11A illustrates an example in which the second expansion groove 440 is formed in multiple numbers in the circumferential direction. Thus, a desired region of the sliding surface between the rotor 500 and the second head portion 400 may be locally and intensively lubricated.

In addition, FIG. 11B illustrates an example of a configuration in which the oil is decompressed and discharged over all of an intake stroke and a compression stroke.

Furthermore, FIG. 11C illustrates an example in which connection grooves 450 to radially connect the first expansion groove 430 and the second expansion groove 440 is further formed in the example shown in FIG. 11B.

Meanwhile, FIG. 11D illustrates an example in which the second expansion groove 440 is formed in the form of an involute curve to extend outwards from the first expansion groove 430. Thus, it may be possible to increase a decompression effect since the second expansion groove 440 is continuously formed radially outwards.

Various embodiments have been described in the best mode for carrying out the invention.

In accordance with a vane rotary compressor according to an embodiment of the present invention, since an entire housing is configured of a 3-piece structure including a cylinder, a housing, and a second head portion, it may be possible to achieve a reduction in costs and weight lightening of a vehicle due to a reduction in the number of parts.

In addition, since a vane rotary compressor has a configuration such that a space between a cylinder portion of a housing and a cylinder is divided into a high-pressure chamber, from which a high-pressure refrigerant is discharged, and a low-pressure oil storage chamber in which oil included in the refrigerant is separated and stored, it may be possible to miniaturize the compressor due to a reduction in the overall length of the package.

Furthermore, since a decompression passage is formed from a gap of a sliding surface between a rotor and a head portion and an expansion groove of the head portion, it may be possible to reduce manufacturing costs because a need for a complicated process to form the decompression passage, as in the related art, is obviated. 

What is claimed is:
 1. A vane rotary compressor comprising: a hollow cylinder; a housing including a cylinder portion which is formed with a space portion to mount the cylinder, and a first head portion which is formed integrally with the cylinder portion so as to close one axial side of the cylinder portion; a second head portion to close the other axial side of the cylinder portion; a rotor which is mounted within the cylinder and rotates by the power of a drive source; a plurality of vanes which protrudes from an outer peripheral surface of the rotor toward an inner peripheral surface of the cylinder and divides a hollow portion of the cylinder into a plurality of compression chambers; a high-pressure chamber which is formed in one side of the housing, into which a high-pressure refrigerant compressed in each of the compression chambers is discharged, and which is formed with a discharge hole communicating with a discharge port; and an oil storage chamber which is formed in the other side of the housing and stores oil separated by an oil separation pipe provided at the discharge port.
 2. The vane rotary compressor according to claim 1, wherein the high-pressure chamber includes a muffler space which is formed to protrude from one side of an outer peripheral surface of the cylinder portion, and the discharge hole is formed at one side of the muffler space.
 3. The vane rotary compressor according to claim 1, wherein the oil storage chamber is formed on an outer peripheral surface of the housing to radially protrude therefrom.
 4. The vane rotary compressor according to claim 1, wherein an oil guide hole is formed to extend from one side of the oil storage chamber to one side of a mounting groove to which a rear end of a rotational shaft of the rotor is mounted.
 5. The vane rotary compressor according to claim 4, wherein a first expansion groove is formed along an edge of the mounting groove.
 6. The vane rotary compressor according to claim 5, wherein a second expansion groove is formed in the form of an involute curve to extend radially outwards from one side of the first expansion groove.
 7. The vane rotary compressor according to claim 6, wherein the rotor is formed with a plurality of oil passages which axially penetrates the rotor so as to communicate with the second expansion groove, and the second expansion groove is located at a position corresponding to the oil passages.
 8. The vane rotary compressor according to claim 7, wherein an extension groove is formed along an edge of an insertion hole into which a front end of the rotational shaft is inserted, so as to communicate with the oil passages.
 9. The vane rotary compressor according to claim 5, wherein at least one second expansion groove is spaced radially outwards from the first expansion groove and formed along a circumferential direction thereof.
 10. The vane rotary compressor according to claim 9, wherein the second expansion groove is formed in the form of a circular arc corresponding to a region between a suction hole and an outlet formed at one side of the cylinder in a compression rotation direction of the rotor.
 11. The vane rotary compressor according to claim 9, wherein the rotor is formed with a plurality of oil passages which axially penetrates the rotor so as to communicate with the second expansion groove, and the second expansion groove is located at a position corresponding to the oil passages.
 12. The vane rotary compressor according to claim 11, wherein an extension groove is formed along an edge of an insertion hole into which a front end of the rotational shaft is inserted, so as to communicate with the oil passages.
 13. The vane rotary compressor according to claim 1, wherein one end of each of the vanes is hinge-coupled to one side of the outer peripheral surface of the rotor, and the other end thereof comes into contact with the inner peripheral surface of the cylinder, depending on the rotation of the rotor.
 14. The vane rotary compressor according to claim 13, wherein the inner peripheral surface of the cylinder is formed in the form of an involute curve along a circumferential direction thereof. 